- #Mac os x terminal emulator serial port for mac#
- #Mac os x terminal emulator serial port serial#
- #Mac os x terminal emulator serial port driver#
- #Mac os x terminal emulator serial port software#
- #Mac os x terminal emulator serial port windows#
#Mac os x terminal emulator serial port serial#
The terminal server cards had 8 serial ports, and we could program them to set up a permanent link between two ports on cards in different locations.
(We also used statistical multiplexers on leased 9600/19200 lines, but that's another mess)īack then we used networking gear from Ungermann Bass.(19" cabinet that slotted in at the bottom of our racks) and in these we inserted all kinds of fun cards.īRI(bridges), routers, ETH(Ethernet cards, 12 or 24 ports) and TRM(Terminal servers). And serial printers for printing, of course. we had Norsk Data ND mainframes at the office, and used terminals to access them. USB to serial works much better mainly because it's assumed to be a mostly dedicated channel so there is less overhead to build a block and it's not shy about building blocks around individual characters, and it is much quicker to detect that an error occurred.īack in the heydays of. The basic problem is that serial is a character based medium where reception is either instantaneous or fails completely, and some serial protocols (including some I've written) depend on this behavior, but ethernet is a block medium where many characters are sent at once, there is significant overhead for sending a block so you want to collect enough of them before sending a block to make the block worthwhile, and you might not start to realize until hundreds of milliseconds later that something might be wrong. You could also use UDP or a non-transportable raw ethernet protocol to get much better timeouts performance.
#Mac os x terminal emulator serial port software#
I've abused the web and email servers in an AnyBus-S card to get much better turnaround on a continuous data stream, but that requires significant custom software at the PC to make use of the data. It is possible to get better performance for specific applications. I have put several of these things in service over the years and in the end I've taken every one of them out. The problem with this is that if a packet gets lost, the TCP/IP timeouts are horrendous - it can take many seconds for the channel to unfreeze.
#Mac os x terminal emulator serial port driver#
All most of these devices do is open a raw socket, which is supposedly a 'virtual serial port', and all the software driver does is map the OS serial API to the TCP/IP API so attempts to use the serial port get routed to the raw socket.
#Mac os x terminal emulator serial port for mac#
(as a side note, I see there are plenty of USB to serial port devices for Mac, I'd imagine a ethernet to serial device would use some similar OS mechanisms, but perhaps there just hasn't been enough of a need for Mac based ethernet to serial devices.)Įthernet to serial doesn't work very well. I figured the gurus on the forum could shed light on this and educate me. I'm guessing it might have something to do with the way the operating system is or how it handles I/O such as serial ports or maybe it is because there isn't enough demand.
#Mac os x terminal emulator serial port windows#
Plenty of devices/drivers for Windows and Linux, but I don't see references to Mac. Recently I've been doing some research into devices to see what the latest devices are on the market and wondering why there isn't such a device for Apple/Mac based computers. Then any software that uses a serial port on the PC can access and control the device just as it was connected to the serial port. One is a physical ethernet device itself which also has one or more serial ports and the other part of the product is software that runs on the PC and makes this ethernet device appear as a serial port to the PC. There are usually two parts to the product. There are several products out there, some of the better known ones include products from Digi. I've used these in many industrial applications and even a few home applications when doing data collection.
These devices have been primarily for Windows/PCs. I suspect this was the first item I encountered because I was in a group of primarily windows software developers dealing with scanners for bar codes. One of the first industrial automation devices I learned about many years ago was ethernet to serial devices. There used to be a sandbox thread, but this appears to be it now. Boy - I haven't been to the forums in a while.
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